Baclofen is a skeletal muscle relaxant and antispastic agent. Baclofen is a structural analog of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA), and may exert its effects by stimulation of the GABAB receptor subtype.
Lioresal™ Intrathecal (baclofen injection) has been developed for chronic intrathecal infusion for the management of severe spasticity. Baclofen is commercially available for intrathecal injection (Lioresal™ Intrathecal) as a 0.05 mg/mL solution, a 0.5 mg/mL solution or a 2 mg/mL solution having a pH of 5 to 7 in a formulation containing sodium chloride and water.
An oral baclofen solution was previously approved by the UK Medicines and Healthcare Products Regulatory Agency. The solution contained, among other ingredients, citric acid monohydrate and sodium citrate dihydrate. The instructions for the solution specified that it was not to be refrigerated or frozen.
There is a continuing need for safe and effective oral baclofen solutions.